Well tools



July 28, 1964 c, c, BROWN 3,142,338

WELL TOOLS Filed Nov. 14, 1960 4 Sheets-Sheet 1 C/CERO C M W/3 IN VEN TOR.

BY ZL M 7 A TTO/ENE Y5 July 28, 1964 c. c. BROWN 3,142,338

WELL TOOLS Filed Nov. 14, 1960 4 Sheets-Sheet 2 C/CERO C. BROWN INVENTOR.

BY 7h.

ATTORNEYS July 28, 1964 c. c. BROWN 3,142,338

WELL TOOLS Filed Nov. 14, 1960 v 4 Sheets-Sheet 3 C/CERO c. ERUIVI/ IN I, EN TOR.

ATTORNEYS V y 8, 1964 c, c. BROWN 3 3,142,338

mam. TOOLS Filed Nov. 14, 1960 4 Sheets-Sheet 4 INVENTOR. 311M A TTORNE Y5 CICERO C BROWN United States Patent 3,142,338 WELL TOOLE Cicero C. Brown, Box 19236, Houston, Tex. Filed Nov. 14, 1960, Ser. No. 69,118 16 Claims. (Cl. 166-420) This invention relates to new and useful improvements in well tools. I

This application is filed as a continuation-in-part of my co-pending application Serial No. 784,503, filed January 2, 1959, now abandoned.

In carrying out various operations within a well bore, it is desirable to provide a well tool such as a well packer which may be set within the well bore and which, when in a set position, is locked against movement in either direction. T o accomplish such locking action, two sets of gripping elements or slips are employed, one for holding the packer assembly against downward movement and the other for holding said assembly against upward movement. With the double slip arrangement, release of the packer assembly to permit its removal from the bore after it has served its function presents a problem and it has been the practice to make this type of packer permanent or nonremovable, with the result that removal can be accomplished only by drilling up all or part of the assembly which, of course, destroys the device.

It is, therefore, one object of this invention to provide a well packer assembly having means for locking the same against movement in either direction within the well bore, together with means for readily releasing the locking means to permit removal of the complete assembly from the well bore whenever such removal is desired.

Another object is to provide a well packer assembly having upper and lower gripping elements for locking the assembly against movement in either direction within a well bore, wherein said gripping elements are moved into set or gripping position by a hydraulic means and are retracted into a released or nongripping position by a mechanical means which is actuated by manipulation of the pipe string upon which the packer assembly is mounted.

An important object of the invention is to provide a well packer assembly, of the character described, wherein the gripping elements are moved into set or gripping position by the application of a suitable pressure and are constructed to remain in set position even though the pressure, which initially moved said elements to such set position, is relieved; the assembly also including normally inactive mechanical means which is adapted, upon rotation of the pipe string carrying the packer assembly, to apply mechanical pressure to the gripping element units in a direction eifecting release of said gripping elements from a gripping position.

A particular object is to provide a packer assembly of the character described in which the mechanical releasing means comprises a pair of members having threaded engagement with each other and having means co-acting with the gripping slip units of the assembly, whereby upon a rotation of one of the members with respect to the other, a jacking action is produced which applies sufficient mechanical pressure to the gripping slip units to assure retraction of the gripping slips to a released position.

Other objects will hereinafter appear.

The construction designed to carry out the invention.

will be hereinafter described, together with other features thereof.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown, and wherein:

FIGURE 1 is a view partly in section and partly in elevation of a well packer constructed in accordance with the invention and illustrating the various parts in the position which they assume during lowering of the device into the well bore;

FIGURE 2 is a similar view showing the packer elements moved into initial set position and prior to setting of the gripping means;

FIGURE 3 is a similar view illustrating the packer elements and gripping means in fully set position;

FIGURE 4 is a view similar to FIGURE 1 showing the lower gripping means and packer elements retracted;

FIGURE 5 is a similar view with the various parts of the assembly in fully retracted position;

FIGURE 6 is a peripheral cross-sectional view taken on the line 66 of FIGURE 1;

FIGURE 7 is a horizontal cross-sectional view taken on the line 7--7 of FIGURE 1;

FIGURE 8 is a view similar to FIGURE 1 and illustrating a slightly modified form of the invention, the parts of the tool being shown in position prior to setting of the gripping means; and

FIGURE 9 is a View similar to FIGURE 8 with the tool in fully set position.

In the drawings the letter A designates the improved well tool assembly which is adapted to be connected in a well pipe string by which the assembly may be lowered into the usual well casing 11. The well tool assembly A is lowered to the desired elevation within the well casing and is adapted to be set therein to be locked against movement in either direction longitudinally of said casing. When desired, the lowering pipe 10 may be manipulated to effect a release of the assembly, after which the assembly may be removed from the well casing by means of said pipe 10.

The well packer assembly includes a central tubular support or mandrel 12 which comprises an upper tubular section 12a and a lower tubular section 1212. The sections are connected together in telescoping relationship by relatively coarse threads 13 which are preferably lefthand. With such arrangement, when the lower section 12b is held stationary, a right-hand rotation of the upper section 12a will result in moving the sections axially in a direction to separate said sections. The upper section 12a is provided with external upwardly facing shoulders 14 and 14a while the section 12b is formed with external downwardly facing shoulders 15 and 15a.

The upper end of the section 12a of the support 12 is connected through a coupling 16 with the upper portion of the lowering pipe 10 while the lower end of the section 1212 has connection through a coupling 17 with the lower portion of the pipe 10. The tubular support 12 forms the main mandrel or supporting element of the complete packer assembly A.

A lower sleeve-like packer element 18 surrounds the lower end of the support 12 and rests upon the upper end of the coupling 17. The packer element is constructed of rubber, rubber compound or other elastic material and when in a normal undistorted position, has its external surface spaced from the wall or bore of the well casing 11. A lower gripping means or unit B is located immediately above the packer element 18 and such unit includes an annular expander 19, the lower end of which is supported upon the packer element 18. As shown in FIGURE 1, the expander element 19 is disposed below the external downwardly facing shoulder 15 on the lower section 12b of the support 12. To prevent rotation of the expander 19 with respect to the section 12b, said section is formed with longitudinal splines 20 (FIGURE 7) which engage recesses 21 provided in the bore of the expander 19. The longitudinal extent of each spline 20 is indicated by the dotted lines in FIGURE 1. At spaced radial points, the expander 19 is formed with inclined expander surfaces 22 and as illustrated three such surfaces are provided.

Co-acting with the inclined expander surfaces 22 are a plurality of gripping elements or slips 23. Each slip has an inclined inner surface 23a which engages and rides upon the inclined expander surfaces 22 of the expander 19. Outward movement of each gripping slip with respect to the co-acting surface which it engages is prevented by longitudinal ribs 24 formed on each slip member; said ribs engage retaining grooves 24a provided in the expander 19 (FIGURE 7). It will be evident that longitudinal movement of the slips relative to the expander in a direction which will move the slips downwardly will result in a radially outward movement of the gripping slips. Each gripping slip is normally retained in its raised position with respect to the expander 19 by a shear pin 25.

The upper end of each gripping slip 23 is formed with a T-shaped hanger 26 which is adapted to engage within a T-shaped slot 27 formed in the lower end of an annular piston sleeve 28. The piston sleeve 28 surrounds the tubular support 12 and with the assembly in fully retracted position, as shown in FIGURE 1, said sleeve surrounds the threaded joint 13 between the sections 12a and 12b of the support 12. Suitable sealing rings 29 seal between the external surface of the section 12b and the bore of the piston sleeve 28.

A tubular cylinder 31) encircles the piston sleeve 28 and has its lower end normally supported upon an external flange 28a formed on the piston sleeve. The upper end of the cylinder has a cylinder head 31 threaded therein and the bore of this head is sealed with the external surface of the section 12a of the support by suitable sealing rings 32. It is noted that the cylinder head 31 surrounds the tubular section 12a above the upwardly facing shoulder 14a whereby when the parts are in the position of FIGURE 1, the cylinder head is supported upon said shoulder; at this time the lower end of the cylinder is resting on the flange 28a. The parts may be retained in this position by means of a shear pin 33 which extends through the wall of the cylinder 30 and which has its inner end engaged with the piston sleeve just above the flange 28a. The upper end of the piston sleeve has a piston element 28b which has sealing engagement with the wall of the cylinder 30 by means of suitable sealing rings 34.

With the piston sleeve 28 and the cylinder 30 in the position of FIGURE 1, the piston element 28]) is in contact with the cylinder head 31. Pressure fluid from the bore of the tubular support 12 may be introduced into the area below the cylinder head 31 through a fluid inlet port 35 which is formed in the lower section 12b of the support 12. Upon the introduction of a pressure fluid, the cylinder head 31 and the cylinder are urged in an upward direction; at the same time this pressure will act downwardly upon the piston element 28b of the piston sleeve 28 and this will result in moving the parts from the position shown in FIGURE 1, through the position shown in FIGURE 2 and finally to the position shown in FIGURE 3.

For preventing rotation of the cylinder 30 with respect to the piston during such movement and also for limiting the movement of the cylinder relative to the piston, a plurality of guide pins 36, one of which is shown in the drawings, are secured to the cylinder. Each pin 36 extends inwardly to engage within a complementary longitudinal groove 37 which is formed in the exterior of the piston sleeve. As the piston sleeve 28 is urged downwardly, it will apply a downward force to the gripping slips 23 and through the shear pin 25 will apply an endwise compressive force to the lower packer element 18. This will result in a distortion of the packer element 18 into sealing contact with the wall of the well casing in the manner shown in FIGURE 2. Continued application of downward force through the piston sleeve 28 to the slips will shear the pin 25 and, thereafter, the gripping slips 23 will move to a set position. Upon setting of the lower slips, the downward movement of the piston sleeve 28 is arrested and the full pressure within the bore of the cylinder 30 above the piston element 28b will act against the lower end of the cylinder head 31 to urge the cylinder head upwardly along the upper section 12a of the tubular support 12.

An upper gripping slip unit C is mounted on the upper section 12:: of the support 12 above the cylinder 30. As clearly shown in FIGURES l to 5, the upper portion of the cylinder head 31 is formed with a plurality of T-shaped slots 33 which are engaged by T-shaped connectors 39 formed on the lower end of upper gripping slips 40 of said unit C. The slips 40 are of similar construction to the slips 23 except they are reversed and each slip 40 is adapted to co-act with an expander surface 41 formed in an annular expander 42. The annular expander 42 urrounds the section 12a of the support 12, being located above the second upwardly facing shoulder 14 which is formed on said section and said expander is rotatable on said support. A shear pin 43 normally connects each slip 40 with the expander 42.

An upper packer element 44 is supported upon the expander 42 and is of similar construction to the lower packer element 18. A confining head member 45 confines the upper end of the packer element 44 and surrounds the upper portion of the section 1211 and has a tubular extension 46 which depends therefrom to extend downwardly through the packer element 44 and into a counter-bore 42a formed in the expander 42. Suitable sealing rings 47 seal between the confining head 45 and the exterior of the support.

So that the upper section 12a of the tubular support 12 and the lowering pipe 10, which is connected thereto coupling 16 may be rotated with respect to the confining head 45, upper packer element 44, expander 42 and slips 40, a bearing raceway 48 having ball bearings 49 confined therein is disposed between the lower end of the coupling 16 and the upper end of the head 45. As will be explained, the rotation of the lowering pipe of the upper section 12a with respect to the lower section 12!) of the support will function to actuate the threaded connection 13 between sections 12a and 12b. Such actuation will effect a release of the gripping slips 23 and 40 after such slips have been set.

Since the upper slips 40 are mounted on the cylinder head 31, movement of the cylinder head in an upward direction will result in the application of a force through the slips 40, shear pin 43 and to the lower end of the upper packer element 44. Because the upper end of the element 44 is confined by the head 45 and its contact with the coupling 16, this application of force will result in setting the upper packer as shown in FIGURE 2. Continued application of force will shear the pins 43 and effect a setting of the upper slips.

In the operation of the apparatus, the parts are assembled as shown in FIGURE 1 with the tubular sup port 12 connected in the lowering pipe 10. The upper packer element 44 is supported upon the upper expander 42 which, in turn, rests upon the external shoulder 14 formed on the upper section of the support. The

gripping slips 40 of the upper gripping slip unit C are connected to the upper expander 42 by the shear pins 43 and are thereby maintained in a retracted position.

The cylinder 30 and its head 31 are supported upon the external shoulder 14a of the support, as shown in FIGURE 1, and the piston sleeve 28 has its piston element 28b in abutting relationship to the underside of the cylinder head. The lower end of the piston sleeve 28 rests on the lower slips which are connected through shear pins 25 to the lower expander 19 and thus the piston sleeve and cylinder are held in the position shown in FIGURE 1. If desired, the additional shear pin 33 may be employed to assist in maintaining said piston sleeve and cylinder in this position.

It is noted that at this time the threaded connection 13 between the sections 12a and 12b of the tubular support 12 is fully made up as illustrated in FIGURE 1 and this disposes the downwardly facing external shoulder 15a on the lower section 121) in contact with an internal shoulder formed at the lower end of the bore of the piston sleeve 28. The upper end of the expander 19 is in contact with the external downwardly facing shoulder 15 on the section 12b and the lower packer element 18, which is below the expander 25, is, of course, in its relaxed or undistorted position.

With the parts in the position shown in FIGURE 1, the assembly A is lowered to the proper position within the well casing and when it is desired to set the packer elements of said assembly and the gripping slip units thereof, a closure, which may be in the form of a ball 50, is dropped downwardly through the lowering pipe. This ball passes downwardly through the bore of the tubular support 12 and engages an annular seat 51 which is formed in the lower coupling 17 to close downward flow of fluid through the lowering pipe and bore of the support 12. It is, of course, evident that other types of closures may be employed. After the ball 50 is in position as shown in FIGURE 2, a pressure is built up within the lowering pipe and the bore of the support 12 and this pressure may pass through the radial port 35 into the annular space between the exterior of the support 12 and the bore of the piston sleeve 28. As this pressure builds up within this area, a force is applied against the underside of the cylinder head 31 and at the same time a downward force is applied against the upper end of the piston element 28b so that the pressure tends to move the cylinder head and piston element apart. The shear pin 33, which connects the cylinder 30 and piston sleeve 28, is of lesser strength than the shear pins 25 and 43 which connect the slips 23 and 40 to their respective expanders.

As suificient pressure builds up within the cylinder, the pin 33 is sheared and this permits an upward movement of the cylinder with respect to the piston element 28b and the piston sleeve 28. Actually, there will be movement in both directions, that is, the cylinder will move upwardly and the piston sleeve will move downwardly. By reason of the strength of the shear pins 25, the downward motion of the piston sleeve 28 will apply a force through the slips 23, shear pin 25 and expander 19 to the upper end of the lower packer element 18 whereby said element is distorted radially outwardly into a sealing engagement with the casing 11. At the same time, the upward movement of the cylinder head 31 will transmit an upward force through the upper slips 40, shear pin 43 and expander 42 to apply an endwise force to the upper packer element 44, thereby resulting in a radially outward movement of the upper packer element into sealing engagement with the wall of the casing 11. This position of the parts is illustrated in FIGURE 2 where the packer elements 18 and 44 have been moved into sealing position but the gripping slips have not yet been engaged.

After the sealing elements have been engaged in the manner above described, the continued application of pressure will apply sufficient force to the piston sleeve 28 and the cylinder to shear the pins 25 of the lower slips and the pins 43 of the upper slips. When this occurs, the slips 23 may move downwardly relative to the lower expander and into gripping engagement with the wall of the well casing 11. Also, the upper slips 40 may move upwardly with respect to their expander 42 to also move into gripping position. The packer is then in fullyset position and it will be evident that any pressure from below the device will act to more firmly engage the lower slips 23; any pressure from above the device will merely act to more firmly engage the upper slips 40. The apparatus is thus locked within the well bore against movement in either direction and the pressure within the interior of the sleeve may be relieved and said slips will remain in their set position.

When it is desired to release the packer, it is only necessary to impart a rotation to the upper portion of the lowering pipe 16 and such rotation is imparted to the upper section 12a of the support 12. As has been explained, the lower section 12]; of the tubular support has a spline connection with the lower expander 19 and by reason of this connection 20, 21 and the engagement of the slips with the wall of the casing, the lower section 121) is held stationary. Thus, the upper section 12a of the support may rotate with respect to the lower section and as it does so, the threads 13 which connect the sections cause a longitudinal movement of the sections with respect to each other in the manner shown in FIGURE 4.

As the sections 12a and 12b move apart by reason of the relatively coarse threads which, as pointed out, are preferably left-hand so that a right-hand rotation of the pipe 10 may be employed, the lower section 12b will move downwardly relative to the upper section 12a, which latter section is initially held stationary because the weight of the lowering pipe 10 above the assembly is acting downwardly on the upper expander and is resisting upward movement of said upper expander. As the lower section moves downwardly, the downwardly facing shoulder 15 engages the upper end of the expander, as illustrated in FIGURE 4, and applies a downward force to the expander to release the lower slips from engagement with the pipe.

As the parts reach the position shown in FIGURE 4, the pin 36 On the cylinder 30 has not reached the limit of the slot 37 in the piston 28 and continued rotation of the section 12a will cause a continued downward movement of section 1211 until pin 36 engages the shoulder 28!) formed at the upper end of slot 37. It is pointed out that the continued extension of the sections 12a and 12b in order to move pin 36 to the limit of its slot is possible even after the lower slips have been released because so long as the upper slips and packer are still engaged, the lower section 12b is held against rotation by reason of the connection between the keyed lower expander 19 and the upper slips, which connection is made through the cylinder 30, piston sleeve 28 and slips 23.

Following the engagement of pin 36 with shoulder 28b, a further downward movement of the section 12b upon continued rotation of section 12a is prevented. Therefore the continued rotation will result in the section 12a being moved upwardly against the weight of the tubing which has up to this time been resisting its upward movement and, therefore, the upper section 12a moves upwardly until the packing element 44 is relaxed and the upwardly facing shoulder 14 engages the under side of the upper cone 42. Obviously, the further upward movement of section 12a after shoulder 14 has engaged the upper expander results in pulling the cone from under the upper slip to complete the release of the upper slips 40. At this time both the lower and upper slips are released. It is of course necessary that the length of the threaded connection between the sections 12a and 12b be of sufiicient length to accomplish the foregoing functions.

The action of the mechanical releasing means is illustrated in FIGURES 4 and 5. In FIGURE 4 the lower expander has been moved downwardly relative to slips 23 to release said slips while the upper expander is still engaged with the slips 40 and is holding the upper slips in gripping position. However, by the time the parts reach the position of FIGURE 5, the pin 36 has traversed the full length of the slot 37 and the upper shoulder 14 on section 12a has engaged the upper cone with the result that an upward movement of the upper expander with respect to the slips has been effected to release said slips; when the shoulder 14a engages the underside of the cylinder head 31, further movement of the sections 12a and 12b cannot occur. upper and lower slips as well as the packing elements 18 and 44 have been retracted and the device may be removed from the well casing by merely lifting and removing the pipe from said bore.

In the form of the invention shown in FIGURES 1 through 7 and as above described, the lower gripping slips 23 are initially connected to the expander cone 19 by the shear pin 25 while the upper gripping slips 48 are initially connected to the expander cone 42 by the shear pins 43. The shear pins 25 and 43 may, as has been noted, he of greater strength than the shear pin 33 which initially connects the piston sleeve 28 with the cylinder 30. However, actual practice has shown that it is not necessary for the shear pins 25 and 43 to be of greater strength than the shear pin 33. The pins 25 and 43 may be of substantially the same strength as pin 33 or in some instances could be of lesser strength. Also pins 25 and 43 could be adjusted to shear prior to the time that the packing elements 18 and 44 are fully expanded.

Where pins 25 and 43 are arranged to shear prior to full expansion of the packing elements 18 and 44, the operation would be as follows: upon the cylinder 30 and piston sleeve 28 moving outwardly from each other by reason of fluid pressure, shearing of pins 25 and 43 would occur before total setting of packing elements 18 and 44. In such instance, the slips 23 would begin to ride downwardly on the inclined surface of expander 19 and upon engaging the wall of the casing 11 would continue to be urged downwardly along said wall. This downward movement would be permitted because the shape of the teeth of slips 23 is such that gripping action is affected only when the slips 23 are moved upwardly. As slips 23 slide downwardly along the wall of casing 11, a force is transmitted through the co-acting surfaces of said slips and the co-acting surfaces of the expander 19 so that the expansion of the lower packing element 18 would be completed.

The action of the upper slips 40 would be the same as above described, that is, after shearing of the pin 43, slips 40 would move upwardly on the cone and would then ride upwardly on the wall of the casing. During such upward movement, sutficient force would be transmitted to the upper packing element 44 to complete setting of said upper packer. The parts would finally assume the position of FIGURE 3 when the device is in fully set position.

Not only is it possible to vary the strength of the shear pins 25 and 43 but such pins can be entirely omitted and such arrangement is illustrated in FIGURES 8 and 9. In these figures, like numerals have been applied to similar parts and the form shown is substantially the same as the first form. This form includes the main mandrel 12, a lower slip assembly B, a lower packing element 18, an upper slip assembly C and an upper packing element 44. The shear pins 25 and 43 of the first form which initially connect the slips to their respective expanders are omitted.

In the form shown in FIGURES 8 and 9, the lower expander is modified in that an annular expander 19a is substituted for the expander 19. The expander 19a rests upon the upper end of the lower packing element 18 and has its outer inclined surface co-acting with the inner inclined surface 23a of the slips 23. Instead of connecting with the main mandrel through a spline connection, as in FIGURE 1, the expander 19:: has connection with a tubular extension 17a provided on the lower coupling 17. The extension 17a is formed with a slot 100 and a pin 101 which is secured in the expander 19a extends into and is movable within said slot. The pin 101 and slot 100 set up a nonrotative connection between the lower expander 19a and main mandrel 12, such connection being completed through the coupling 17 and the lower section 12b of said main mandrel; however, the expander may undergo limited axial movement with re- However, by this time both spect to the mandrel in accordance with the length of the slot 100. The pin and slot connection perform the same function as the spline connection 20 (FIGURE 7) of the first form in that the lower expander is nonrotatable with respect to the mandrel while allowing limited axial movement of the mandrel and expander relative to each other. When employing the pin and slot connection, it is possible to omit the external shoulder 15 on the mandrel section 12b, which shoulder functions to confine upward movement of expander 19 on said section.

The operation of the modified form of the invention is substantially the same as that heretofore described. With the parts in the position of FIGURE 8 during lowering of the well tool, the cylinder head 31 of cylinder 30 is supported on the shoulder 14a of the main mandrel 12. The upper gripping slips 40 are supported upon said cylinder head while the lower slips are suspended therefrom. Since the packing elements 44 and 18 are relaxed, their respective expanders 42 and 19a are in a position with the slips 23 and 40 retracted (FIGURE 8).

Upon dropping of the ball 50 indicated in dotted lines in FIGURE 9 and the application of pressure through the port 35, the piston sleeve 28 and the cylinder 30 are extended. This movement urges the slips 40 upwardly with respect to the expander 42 and at the same time urges the slips 23 downwardly with respect to the expander 19a. As the upper slips move into engagement with the wall of the casing 11, said slips will thereafter ride upwardly on the casing wall to transmit a force through the expander sufficient to deform the upper packing element 44 into sealing position. This action takes place because of the particular shape of the teeth of slips 40 which allows upward sliding movement of the slips along the wall while preventing reverse or downward movement of said slips.

At the same time the lower slips 23 are moved downwardly into contact with the casing wall after which they will slide along said wall in a downward direction to transmit sutficient force through the expander 19a and against the lower packing element 18 to expand the latter. The shape of the teeth on the slips 23 allows downward sliding movement of these slips while preventing any reverse or upward motion thereof. As the lower expander 19a moves downwardly, the pin 101 travels within slot 100. The fully set position of the tool is shown in FIGURE 9.

Release of the tool shown in FIGURES 8 and 9 is effected in the same manner as the release of the first form. The upper section 12a of the main mandrel 12 is rotated relative to the lower section 12b and since the lower section is nonrotatably connected through coupling 17 with the lower expander 19a, the lower section 12b is held against rotation. As the sections are rotated relative to each other, the threads 13 effect a longitudinal movement of said sections, whereby the shoulder 14 moves beneath the upper expander 40 and the pin 101 is engaged by the upper limit of the slot 100.

Although it may be that one or the other of the expanders is released first, the continued rotation of the section 12a relative to section 12b results in a jacking action which moves each of the expanders from beneath its respective slips, whereby the parts are returned to the position of FIGURE 8. In such position, the upper and lower slips and their adjacent packing elements are fully released and the tool may be removed from the well bore.

It is pointed out that the well packer assembly is relatively simple in construction and provides upper and lower gripping means which will function to lock the assembly within the well bore against movement in either direction to provide a permanent-type packer. The gripping means is initially moved into a set position by the application of fluid pressure and is maintained in such position by the pressures acting against the packer elements. Therefore, even though the setting pressure within the cylinder is relieved, the packer elements and the gripping slip units 9 remain in set position. Subsequently, when it is desired to release the gripping means, it is only necessary to manipulate the lowering pipe and effect a mechanical release of both the upper and lower slips whereby the entire assembly may be removed from the well bore.

The foregoing disclosure and description of the invention is illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made within the scope of the appended claims without departing from the spirit of the invention.

What I claim is:

l. A well tool assembly including, a tubular support adapted to be connected in a Well pipe string and lowered in a well bore, an upper gripping means mounted on the support and movable into gripping position to lock the assembly against movement in one direction within the well bore, a lower gripping means mounted on the support and movable into gripping position to lock the assembly against movement in the other direction within said well bore, a hydraulically-actuated part mounted on the support and engageable with the upper gripping means to move said gripping means into gripping position when said part is actuated, a second hydraulicallyactuated part mounted on the support and engageable with the lower gripping means to move said lower gripping means into gripping position when said part is actuated, the tubular support having means for conducting pressure fluid from the tubular support to the hydraulically-actuated parts to operate the same and thereby move the upper and lower gripping means into gripping position, and normally inactive means forming part of the tubular support adapted when actuated to engage and co-act with the upper and lower gripping means for retracting said upper and lower gripping means to permit removal of the complete assembly from the well bore, said normally inactive means being actuated by manipulation and movement of the pipe.

2. A well tool assembly including a tubular support adapted to be connected in a well pipe string and lowered in a well bore, an upper gripping means mounted on the support and movable into gripping position to lock the assembly against movement in one direction within the well bore, a lower gripping means mounted on the support and movable into a gripping position to lock the assembly against movement in the other direction within said well bore, a hydraulically-actuated part mounted on the support and engageable with the upper gripping means to move said gripping means into gripping position when said part is actuated, a second hydraulically-actuated part mounted on the support and. engageable with the lower gripping means to move said lower gripping means into gripping position when said part is actuated, the tubular support having means for conducting pressure fluid from the tubular support to the hydraulically-actuated parts to operate the same and thereby move the upper and lower gripping means into gripping position, a pair of force-applying sections forming part of said tubular support, said sections being in telescoping relationship to each other and being normally in a first retracted position, means actuated by a manipulation and movement of the well pipe string to which the tubular support is connected for moving the force-applying sections to a second extended position, and means on said sections engaging and co-acting with the upper and lower gripping means when said sections are moved to extended position to release said gripping means from gripping position whereby the entire assembly may be removed from the well bore.

3. A well tool assembly as set forth in claim 2, wherein the force-applying sections comprise tubular members which are connected together in telescoping relationship by relatively coarse threads, said threads functioning to move the members to extended position upon rotation of one of said members relative to the other, and means di- 10 rectly connecting one of the members to the well pipe string, whereby rotation of said string efiects a movement of the members to an extended position.

4. A well tool as set forth in claim 1, together with releasable means associated with the upper gripping means to normally maintain the same in retracted posi tion, and additional releasable means associated with the lower gripping means for maintaining the lower gripping means in retracted position, said releasable means for both the upper and lower gripping means being released upon a predetermined application of pressure to the hydraulically-actuated parts whereby said pressure first releases the releasable means and thereafter moves the gripping means into gripping position.

5. A well tool assembly including, a tubular support adapted to be connected in a well pipe string and lowered in a well bore, an upper gripping means mounted on the support and movable into a gripping position to lock the assembly against movement in one direction within the well bore, a lower gripping means mounted on the support and movable into the gripping position to lock the assembly against movement in the other direction within said well bore, hydraulically-actuated means on said support between the upper and lower gripping means and having a connection with said gripping means, whereby operation of said hydraulically-actuated means moves said gripping means into gripping position, the tubular support having means for conducting pressure fluid from the bore of the well pipe to which the support is connected to said hydraulically-actuated means to operate the same and thereby move the upper and lower gripping means into gripping position, and normally inactive means forming part of the tubular support adapted when actuated to engage and co-act with the upper and lower gripping means for retracting the upper and lower gripping means to permit removal of the complete assembly from the well bore, said normally inactive means being actuated by manipulation and movement of the pipe.

6. A Well tool assembly including, a tubular support adapted to be connected in a well pipe string and lowered in a well bore, an upper gripping means mounted on the support and movable into gripping position to lock the assembly against movement in one direction with the well bore, a lower gripping means mounted on the support and movable into a gripping position to lock the assembly against movement in the other direction within said well bore, a hydraulically-actuated part mounted on the support and engageable with the upper gripping means to move said gripping means into gripping position when said part is actuated, a second hydraulically-actuated part mounted on the support and engageable with the lower gripping means to move said lower gripping means into gripping position when said part is actuated, the tubular support having means for conducting pressure fluid from the tubular support to the hydraulically-actuated parts to operate the same and thereby move the upper and lower gripping means into gripping position, the tubular support including an upper member and a lower member telescoping said upper member and having threaded engagement therewith, one of the members of said support being rotatively coupled to the upper gripping means and the other of said members being mounted to rotate with respect to the other gripping means, whereby relative rotation of said members causes movement of the members in an axial direction with respect to each other, said members being normally in a first position in substantially fully telescoped position, relative rotation of the members extending said members to a second extended position, and means on the upper and lower members co-acting with the upper and lower gripping means when said members are moved to extended position to release the gripping means from gripping position whereby the entire assembly may be removed from the well bore.

7. A well tool assembly including, a tubular support adapted to be connected in a well pipe string and lowered into a well bore, said support comprising an upper tubular section and a lower tubular section, means connecting the upper and lower sections in telescoping relationship to each other and normally maintaining the sections in a first fully telescoped position, said connecting means being operable by manipulation of the pipe string to which the support is connected for moving the sections axially with respect to each other to a second extended position, upper gripping means rotatively mounted on the upper section of the support, lower gripping means nonrotatively mounted on the lower section of the support, hydraulically-actuated means having parts coacting with the upper and lower gripping means to move the same into gripping position when said hydraulically-actuated means is actuated, the tubular support having means for conducting pressure fluid from the bore of the support to operate said hydraulically-actuated means and thereby set said upper and lower gripping means, means on the upper section of the support engageable with the upper gripping means to release the same from set position, and means on the lower section of said support engageable with the lower gripping means to release the same from said position, said means being engageable with said upper and lower gripping slips when the sections are moved to an extended position.

8. A well tool assembly as set forth in claim 1, together with an upper packer element disposed above and in contact with the upper gripping means, means confining that end of said packer element which is remote from the gripping means whereby when the upper gripping means is moved into gripping position the packer element is deformed into sealing position, a lower packer element disposed below and in contact with the lower gripping means, and means confining that end of said lower packer element which is remote from the lower gripping means whereby when the lower gripping means is moved into gripping position the lower packer element is deformed into sealing position.

9. A well tool assembly as set forth in claim 5, together with an upper packer element disposed above and in contact with the upper gripping means, means confining that end of said packer element which is remote from the gripping means whereby when the upper gripping means is moved into gripping position the packer element is deformed into sealing position, a lower packer element disposed below and in contact with the lower gripping means, and means confining that end of said packer element which is remote from the gripping means whereby when the lower gripping means is moved into gripping position the lower packer element is deformed into sealing position.

10. A well tool assembly including, a tubular support adapted to be connected in a well pipe string and lowered into a well bore, said support comprising an upper tubular section and a lower tubular section, means connecting the upper and lower sections in telescoping relationship to each other, and normally maintaining the sections in a first fully telescoped position, said connecting means being operable by manipulation of the pipe string to which the support is connected for moving the sections axially with respect to each other to a second extended position, a lower gripping slip unit carried by the lower section of the tubular support, said lower gripping slip unit comprising an expander, means for nonrotatively mounting the expander on said section and gripping slips co-acting with the expander whereby relative movement of said slips and said expander moves the gripping slips outwardly into gripping position, an upper gripping slip unit mounted on the upper section of the tubular support, said gripping slip unit comprising an expander surrounding the upper section of the support, means for rotatively mounting the expander on said upper section and gripping slips co-acting with the expander whereby relative movement between the slips and expander displaces said slips into gripping position, hydraulically-actuated means surrounding the support and located between the upper and lower gripping slip unit, the tubular support having means for conducting a pressure fluid to the hydraulicallyactuated means to operate the same and apply a force to the gripping slip units to effect relative movement of the slips with respect to their expanders and thereby set the same, means on the lower section of the support engageable with the expander of the lower gripping slip unit to release the gripping slips thereof from gripping position, and means on the upper section of said support engageable with the expander of the upper gripping slip unit to release the gripping slips thereof from gripping position said means being engageable with said upper and lower expanders when the sections are moved to an extended position.

11. A well tool assembly as set forth in claim 10 wherein the hydraulically-actuated means comprises a cylinder and a tubular piston movable within the cylinder, with both piston and cylinder surrounding the support, said cylinder and said piston being moveable relative to each other upon the application of hydraulic pressure and having their extremities engaged with the gripping slips of the upper and lower gripping slip units, whereby said gripping slips are moved with respect to their expanders to displace the gripping slips into gripping position.

12. A well tool assembly as set forth in claim 10 together with an upper packer element adjacent the upper gripping slip unit and a lower packer element adjacent the lower gripping slip unit, and means confining that end of each packer element which is remote from the gripping slip unit adjacent that packer element for distorting the packer elements into sealing position when the gripping slips of said units are moved into gripping position.

13. A well packer assembly including, a tubular support adapted to be connected in a well pipe string and lowered into a well bore, said support comprising an upper tubular section and a lower tubular section, means connecting the upper and lower sections in telescoping relationship to each other and normally maintaining the sections in a first fully telescoped position, said connecting means being operable by manipulation of the pipe string to which the support is connected for moving the sections axially with respect to each other to a second extended position, a lower resilient packer element mounted on the lower section of the support, an annular slip expander supported on the upper end of the packer element, a plurality of gripping slips engaging the expander and adapted to be moved into gripping position when the slips are moved in one direction relative to the expander and to be retracted when moved in an opposite direction, releasable means normally connecting the slips to the expander in a retracted position, a movable annular piston surrounding the support and having its lower end connected to the gripping slips, a cylinder surrounding the annular piston and having a cylinder head at its upper end in sealing engagement with the upper section of the tubular support, said support having means conducting fluid pressure from the bore of the support into the cylinder, upper gripping slips connected to the upper end of the cylinder, an upper annular expander surrounding the upper section of the tubular support and adapted to coact with the slips to move the slips radially outwardly into gripping position when the expander and slips are moved in one direction with respect to each other and to retract said slips when the parts are moved relative to each other in an opposite direction, releasable means normally connecting the upper slips to the upper expander with the slips in a retracted position, an upper resilient packer element supported upon the upper expander, confining means carried by the upper section of the support and engaging the upper end of the upper packer element, introduction of fluid pressure into the cylinder resulting in movement of the annular piston in a downward direction and a movement of the cylinder in an upward direction whereby a force is applied to the gripping slips and expanders to eifect distortion of the upper and lower packer elements into sealing position, continued application of pressure after said packer elements have been set effecting a release of the releasable means between the slips and their respective expanders, whereby said slips are moved into a gripping position, abutment means on the upper section of the tubular support engageable with the upper expander to move the same from between the upper slips, abutment means on the lower section of the support engageable with the lower expander to move said expander from between its slips, said abutment means being engageable with said upper and lower expanders when the sections of the tubular support are moved to an extended position.

14. A well packer assembly as set forth in claim 13 together with frangible means between the cylinder and the annular piston for normally maintaining the cylinder and piston in a position which applies no force to the gripping slips of said gripping slip units.

15. The combination with a permanent type well tool assembly having an upper gripping slip unit and a lower gripping slip unit for locking the assembly against movement in either direction within a well casing, of a releasing apparatus comprising, a tubular support extending entirely through said assembly, said support comprising an upper section and a lower section which telescope each other and which are normally in a first fully telescoped position, said sections being movable to a second extended position, the upper section being rotatable within the upper gripping slip unit and having an abutment which is spaced from said unit when the sections are in their first fully telescoped position, means nonrotatively connecting the lower section with the lower gripping unit while permitting axial movement with respect thereto, said lower section having an abutment thereon which is spaced from the lower gripping Slip unit when the sections are in their first fully telescoped position, and means for moving the sections of said support to their second extended position to engage the abutments thereon with the gripping slip units to thereby eifect a release of said units from gripping position.

16. The combination as set forth in claim 15, together with a lowering pipe connected to the upper section of the support, said means for moving the sections to their second extended position being operable by manipulation of said lowering pipe.

References Cited in the file of this patent UNITED STATES PATENTS 1,802,525 Newlin Apr. 28, 1931 2,762,441 Newlin Sept. 11, 1956 2,845,127 Breaux July 29, 1958 1 2,878,877 Baker Mar. 24, 1959 

1. A WELL TOOL ASSEMBLY INCLUDING, A TUBULAR SUPPORT ADAPTED TO BE CONNECTED IN A WELL PIPE STRING AND LOWERED IN A WELL BORE, AN UPPER GRIPPING MEANS MOUNTED ON THE SUPPORT AND MOVABLE INTO GRIPPING POSITION TO LOCK THE ASSEMBLY AGAINST MOVEMENT IN ONE DIRECTION WITHIN THE WELL BORE, A LOWER GRIPPING MEANS MOUNTED ON THE SUPPORT AND MOVABLE INTO GRIPPING POSITION TO LOCK THE ASSEMBLY AGAINST MOVEMENT IN THE OTHER DIRECTION WITHIN SAID WELL BORE, A HYDRAULICALLY-ACTUATED PART MOUNTED ON THE SUPPORT AND ENGAGEABLE WITH THE UPPER GRIPPING MEANS TO MOVE SAID GRIPPING MEANS INTO GRIPPING POSITION WHEN SAID PART IS ACTUATED, A SECOND HYDRAULICALLYACTUATED PART MOUNTED ON THE SUPPORT AND ENGAGEABLE WITH THE LOWER GRIPPING MEANS TO MOVE SAID LOWER GRIPPING MEANS INTO GRIPPING POSITION WHEN SAID PART IS ACTUATED, THE TUBULAR SUPPORT HAVING MEANS FOR CONDUCTING PRESSURE FLUID FROM THE TUBULAR SUPPORT TO THE HYDRAUCLICALLY-ACTUATED PARTS TO OPERATE THE SAME AND THEREBY MOVE THE UPPER AND LOWER GRIPPING MEANS INTO GRIPPING POSITION, AND NORMALLY INACTIVE MEANS FORMING PART OF THE TUBULAR SUPPORT ADAPTED WHEN ACTUATED TO ENGAGE AND 